1. Field of Invention
The present invention relates to vehicular clutch adjustments made to compensate for increased clutch component travel resulting from clutch wear, and to overall enhancements in the utility of automatic wear compensation mechanisms used in clutches for such purposes. More particularly, the invention relates to a device for limiting an otherwise permissible amount of wear adjustment of a centrifugal clutch, so that an over-adjustment condition may be avoided, and potential for damage to critical clutch components may be reduced.
2. Description of the Prior Art
Clutch wear mechanisms of the type affixed to vehicular clutch covers are used to compensate for clutch friction lining wear over the functional life of a clutch. In centrifugal clutches, such mechanisms are typically directly affixed between clutch covers of vehicular clutch assemblies and housings of centrifugal weight and roller modules, and are secured to the respective structures via traditional fasteners, including rivets or bolts.
Although clutch wear compensation mechanisms have improved over time, such mechanisms have not always been successful in protecting critical components of the clutch under conditions of extreme wear, particularly the clutch linings associated with rotary clutch friction plates or discs. In some instances, the fasteners, such as rivets for example, that secure the linings to the discs become exposed after the linings are worn. The exposed rivets then become prone to causing mechanical damage to the flywheel and pressure plate surfaces.
The present invention provides a clutch travel limit or stop for a vehicular clutch to limit amount of clutch travel adjustment otherwise normally permitted for compensation of clutch component wear. The stop is employed in such clutches to limit the amount of permissible wear of the internal clutch components, such as friction disc linings. In addition, the stop is employed to eliminate or reduce the effect of over-adjustment of the clutch via a cam segment wear compensation mechanism.
In one described embodiment, the stop is defined by a protuberance, such as an integrally formed lug, fixed to an outer circumferential periphery of the housing of a centrifugal weight and roller compensation module. The lug is positioned proximally to a clutch flywheel ring or attached clutch cover segment for limiting axial travel of the ring relative to the module housing, and in turn for limiting amount of permissible adjustment of the clutch so that an over-adjustment due to an overworn condition may be avoided. Potential damage to critical clutch components is thereby minimized, such as damage to flywheel and pressure plate components caused by exposed fasteners, such as rivets, after the clutch linings secured by the rivets to the friction disc have become substantially worn.